G-WAN seems again to perform a lot better than the other servers. Nginx always performs slightly better than Lighttpd, while Apache Traffic server is very similar to Lighttpd in term of performance. Finally, Varnish Cache serves only half of the requests compared to all others. Surprisingly , there are quite few differences between the results with optimized settings and those with the default settings.
Regarding the resources used by each server, Nginx is the winner in term of memory usage, as the amount of memory does not increases with the number of concurrent clients. G-WAN requires 2 times less CPU than the other servers.
Again, keep in mind that this benchmark compares only the servers locally (no networking is involved), and therefore the results might be misleading.